This invention relates to automatic tool exchanging apparatus of floor type horizontal milling and boring machines.
Usually, in an existing large size machine tool or a machining center, a tool has been directly exchanged between the spindle and a tool storing magazine arranged near a spindle head. However, in a large machine tool such as floor type horizontal milling and boring machines, since a tool having heavy weight (about 60 kg) and large diameter is used and the spindle of the machine must be displaced in a wide range in X-and Y-directions, it is hardly impossible to manually exchange the tool between spindle and the tool storing magazine in view of working ability and security because if the tool storing magazine is located on the side or top surface of the column of the machine tool having a large height, the receival and removal of tools into and out of the magazine requires much labour and dangerous manual operation.
In order to obviate above described defects, there has been proposed a machine tool, as disclosed in the Japanese Patent Laid Open Specification No. 43285/1974, in which a tool exchanging magazine is mounted on a column base, and tools are conveyed by a tool conveying device along first and second convyers to portion near the spindle head and are automatically exchanged by a tool exchanging arm mounted in the spindle head. However, in this machine, it is inevitable that tools each having a large dimension and a heavy weight are horizontally conveyed under unstable condition.